I have now finished a crude version that manages to get GPS fix and failback to network location if GPS hasn't gotten a fix in 30 seconds.
Features that are needed to enter Beta:
* Some kind of simple lock to disallow changing of secret text if you don't know a PIN
* Turn on ringer and set ringer volume to max once secret SMS is received.
* More detailed message with address-lookup and "last seen" time.
Features that I think would be nice:
* Mail-function if network is available
* Send an SMS / Email every 10 minutes, showing updated location for x hours.
* Blog-API to post updates on a blogger-blog.
* Store track on phone and supply in email/blog updates, to show a nice path in Gmaps.
* Removal of secret SMS so it won't show up in the normal messaging apps.
The new alpha is available at: